SIOUX FALLS, S.D. (AP) - Sioux Falls is moving forward with an environmental assessment and land appraisal ahead of a potential purchase of the 9.5-acre downtown BNSF rail yard site.

The Argus Leader reports that officials have been negotiating since August after Burlington Northern Santa Fe offered to sell the land to the city for redevelopment without requiring construction of a new switching yard.

Public Works Director Mark Cotter outlined the basic terms for property transfer during Tuesday's city council meeting.

The price will be determined by the appraisal and BNSF's calculations. Cotter says the project team is working to ensure costs are below the federally earmarked $35.1 million.

Congress authorized federal money for the project in 2005, and the project was brought before the city council to get local funding approval in 2006.

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